How do alternators on the GX470 fail? (1 Viewer)

[HomersCanyonero]

I'm trying to figure out how important it is to replace the alternator on my 2003 GX470 as preventive maintenance. I'm starting to go offroad into places that are an hour or two from civilization and I have a rebuilt Denso alternator from Amazon sitting in the garage.

What are the symptoms of an alternator going out? Also, is it imperative that I replace my alternator as preventive maintenance?

I've done the timing belt, pulley, water pump, radiator, cap, thermostat, drive belt, upper/lower radiator hoses, replaced all fluids including transmission fluid, new dashboard, and new battery. All within the last 6 months. So, just trying to figure out what to do with the alternator.

 

[GXO]

Usually a voltage drop and a gear whine from the pulley are the signs.

 

[Hoosier Daddy]

Mine made a horrible whine and smelled like electrical arcing. The CEL never came on.

 

[HomersCanyonero]

When alternator starts failing and you hear and smell the said symptoms, does the GX470 start and is drivable?

My real concern is what happens if alternator fails when I’m offroading. Will I be able to limp to a repair shop 100 miles away?

Is there any type of rule of thumb on when to replace alternator if still working fine?

There’s general information out on the web that in general (including all cars) alternators last only like 7 yrs and/or 150k miles, but my 96FZJ80 still running original alternator after 21 yrs and 250k miles.

So, part of me says replace it now, and part of me says wait until it fails to save labor costs and avoid replacing parts that are working fine.

The only extra device I have on GX470 is two front LED fog lights. Everything else that uses battery is stock other than the usb power plugs for iPhone. Most light bulbs inside are now LED.

 

[Hoosier Daddy]

Mine was still charging the battery when it started dying, but only barely. The real risk, of course, from a dead alternator is that your battery will die and leave you stranded. And running a battery dead can damage it, so there's even more risk.

My own personal opinion is that the alternator on the GX should be considered preventive maintenance rather than a repair item, because it is such a common failure point. I always suggest doing it along with the water pump and timing belt (and/or radiator), but it sounds like that ship has already sailed for you.

When you have spare time and good weather, I'd go ahead and replace it, especially since you already have the part.

BTW, you mentioned labor charges. The alternator is an annoying job because of tight clearances, but it is not a technically difficult job. It is a fine DIY project if you've got the time and patience.

 

[chiz45]

You have a 15 year old truck with parts that will eventually give out. In what condition were the parts that you replaced? I saw in your FZJ description you have a blue silicone PHH. I too had one in my 80. I didn't wait until it burst and left me stranded, i had it done. Think of the alternator as a PHH

 

[HomersCanyonero]

LOL on the GX470 alternator = FZJ80 PHH! I'm overthinking this. Since I have the rebuilt alternator in the garage, I'll just replace and keep the old one as my spare.

I'm starting to be anal retentive on preventive maintenance like the rest of everyone on this board. I keep thinking that the Landcruiser Prados in Latin America probably get less than half the preventive care we do here in the USA. These things were built to last.

I know these V8 engines have lasted over 500k miles on 100s and Tundras, so they were well built when properly babied with oil changes, fresh coolant, and I suppose anal retentive preventive maintenance.

 

[Arailt]

*Million mile.

Million Mile Tundra: The Tear Down

Although that motor was built in America, not Japan... so the Japanese motor should be good for two mil, right?

 

[HomersCanyonero]

Wow...a million miles. The real question was the alternator original? ROTFLMAO!

Anyways, I wonder how anal retentive the owner was on preventive care.

 

[Toyoland66]

My own personal opinion is that the alternator on the GX should be considered preventive maintenance rather than a repair item, because it is such a common failure point. I always suggest doing it along with the water pump and timing belt (and/or radiator), but it sounds like that ship has already sailed for you.

I agree, mine failed about 5k after doing the 90k service, same with the radiator. I will do both at each 90k from here forward, it would add about 15min to the job instead of several hours to do after the fact.

Mine had a charging system warning light to notify that it was going bad before it caused any issues.

 

[GonzoShinyPants]

Just my two cents but if you're going that far out from populated areas just get it done. On a prior Honda Accord the alternator died without much if any warning. And then the issue is it's either not charging your battery much or at all and you don't necessarily know that so you don't want to end up with a dead battery. ALTHOUGH, these new charger packs (as I'll call them) will jump a battery so might be a good piece of gear to have anyway.

 

[rz470]

Oh damn after reading all the comments now I am scared driving mine . What is the part number and Where can I get one cheaper than dealer .

 

[HomersCanyonero]

I honestly think we baby these off-road vehicles too much. I got my Denso rebuilt alternator on Amazon for $127 no core exchange required. Denso 210-0512 Remanufactured Alternator

There’s many other places you can also get it from.

 

[Hoosier Daddy]

Mine was a Denso Reman 210-0607 for $167 on Amazon (currently $190). This is the number for trucks built after July 2006.

Oh, and no, you can't buy a new OEM one. Remanufatured is the only option for OEM.

 

[GXO]

I bought a brand new 290A nation starter and alternator. It was expensive, but sealed and very high performance. It makes 180A at 1800 rpms.

 

[BlackCat]

I’m also on my original at 165k. It was literally in the back of my head the whole time I was going thru Death Valley a few weeks ago. It would’ve sucked to be stranded out there.

 

[Dharma Dude]

I am curious. What electrical loads do you all have on your rigs that make you want so many amps out of your alternator?

 

[HomersCanyonero]

I’m just replacing with rebuilt oem at standard 130 amps. I’m just worried that my Xmas LEDs will go out while in Death Valley.

By all, you mean Dan who is running a winch, a fridge, a compressor, dual batteries, and a few other gadgets like rocket boosters. He’s the only one in this thread running a 290A alternator.

 

[White Stripe]

I have seen quite a few have intermittent issues, something along the line of the diodes starting to die and allow ac current through or the regulator spiking. Symptoms of this are battery early death. Also using one of those newer small hand held battery jumpers on such a vehicle will kill the jumper. But it can be intermittent and lead one to think it's just a bad battery, but really the battery is bad because the alternator smoked it. Install a new battery, it works for a time until the alternator acts up again. When I get one in the shop where the battery isn't weak, but totally toast, I install a new battery and Toyota alternator. I used to get about one a month at one of the shops I worked at.

 

[BlackCat]

I am curious. What electrical loads do you all have on your rigs that make you want so many amps out of your alternator?

If you could buy a GX with 400 horsepower for $100 more, would you? Same concept applies to electrical power for people who have fridges, winches, dual batteries, etc.